John Lawler's remains were found in a wooded area near David Drive by a person walking their dog, the Essex County District Attorney said.
Lawler was last heard from in July when he left the Salvation Army rehab center on Broadway in Saugus to purchase fishing supplies, reports said.
Lawler was a lifelong resident of Haverhill and an avid angler.
"Lawler left his home with his fishing rod. All of his belongings including his cell phone were left behind," the National Missing and Unidentified Persons System entry reads. "Lawler was physically fit, often times riding his bicycle and working out at the local gym. He was last seen walking toward Route 1 carrying his fishing pole."
Police did not disclose when he died or what caused his death. The Office of the Chief Medical Examiner is still investigating the case.
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